Electronic electroplating wastewater treatment device with heavy metal recovery function

Abstract

The invention discloses an electronic electroplating wastewater treatment device with a heavy metal recovery function, and relates to the technical field of electroplating wastewater treatment.The electronic electroplating wastewater treatment device comprises a placement frame, sedimentation tanks and filtering tanks, the sedimentation tanks are symmetrically installed at the top of the placement frame, the filtering tanks are fixed to the positions, located at the bottoms of the sedimentation tanks on the single side, of the placement frame, and a first water pump is installed on the placement frame; a water inlet of the water pump I is communicated with the top side of the single-side settling tank through a pipeline; a water outlet of the water pump I is communicated with the bottom side of the filtering tank through a pipeline; through optimized arrangement of the ultrafiltration membrane cylinder and innovative design of a movable sealing cover backwashing mechanism, online directional backwashing and effective collection of a heavy metal concentrated solution are realized; a detection-treatment-recovery integrated solution is constructed by combining an anodic stripping voltammetry online detection system and an intelligent control platform, so that the heavy metal recovery rate and the water resource recycling efficiency are remarkably improved while continuous and stable operation of the system is ensured.

Description

Technical Field

[0001] This invention relates to the field of electroplating wastewater treatment technology, specifically to an electronic electroplating wastewater treatment device that also has heavy metal recovery capabilities. Background Technology

[0002] Electroplating, as an indispensable basic process in modern manufacturing, is widely used in electronics, hardware, aerospace and other fields. It discharges up to 680 million tons of wastewater every year, of which more than 60% contains heavy metals. This wastewater is usually acidic and contains a variety of highly toxic heavy metal ions such as chromium, nickel, copper, zinc and cadmium, as well as complexing agents such as cyanide, EDTA and nitric acid, which cause the metals to exist in a stable complex state, making it difficult for conventional treatment methods to effectively degrade and separate them. Chemical precipitation is currently the most widely used process in electroplating wastewater treatment. This method involves adding FeSO4 to precipitate Cr. 6 Cr is reduced to Cr³⁺, and then the pH is adjusted to generate Cr(OH)₃ precipitate, which can remove Cr. However, the amount of sludge produced is as high as 3-5 kg / m³, and it contains impurities such as CaSO₄ and Fe(OH)₃, making metal resource recovery difficult. In recent years, CaS has been used as a substitute for Cr. x While the sulfidation precipitation method using Na2S as a precipitant can selectively recover Cu and Ni and increase the metal grade to 30%-45%, it has problems such as high cost of sulfiding agents and risk of H2S escape, which limits its large-scale promotion. According to the treatment device for recovering silver, mercury and chromium heavy metals in laboratory waste liquid published in CN218089228U, a combination process of multi-stage pH adjustment tank and sedimentation tank is adopted. This device achieves stepwise precipitation of heavy metals by precisely controlling different pH conditions. Although it improves the metal recovery efficiency, the system requires complex pipeline connections and multiple reaction tanks, the equipment occupies a large area, and the subsequent treatment of precipitated sludge is not solved. Therefore, we propose an electronic electroplating wastewater treatment device that also has the function of heavy metal recovery. Summary of the Invention

[0003] The purpose of this invention is to provide an electronic electroplating wastewater treatment device that also has the function of heavy metal recovery, thereby solving the problems mentioned in the background art; To achieve the above objectives, the present invention provides the following technical solution: an electronic electroplating wastewater treatment device with heavy metal recovery function, comprising a placement rack, a sedimentation tank and a filter tank, wherein sedimentation tanks are symmetrically installed on the top of the placement rack, and a filter tank is fixed on the placement rack and located at the bottom of one side of the sedimentation tank. A water pump is installed on the placement rack, the inlet of the water pump is connected to the top side of the one-sided sedimentation tank through a pipe, and the outlet of the water pump is connected to the bottom side of the filter tank through a pipe. A partition is fixedly connected to the inner wall of the filter tank. Ultrafiltration membrane cartridges are evenly installed on the partition. A transfer cylinder is also installed on the partition on the side of the ultrafiltration membrane cartridges. A transmission tube is movably connected inside the transfer cylinder. One end of the transmission tube passes through the partition and is fixedly connected to a rotating sleeve. A sealing cover is slidably connected inside the rotating sleeve. The sealing cover is correspondingly set with the ultrafiltration membrane cartridges installed on the partition side and is used for receiving and transporting heavy metal concentrate during backwashing.

[0004] Furthermore, the bottoms of the two sedimentation tanks are connected by a pipe, and a dosing tank is installed on the top of one sedimentation tank. A detection channel is installed on the rack, which is located at the front end of the water pump inlet pipe. The equipment installed on the detection channel side uses the anodic stripping voltammetry method to perform online detection of the supernatant in the sedimentation tank.

[0005] Furthermore, a drive motor is installed on the top of the filter tank, and a rotating shaft is installed inside the transfer cylinder. The end of the rotating shaft passes through the transfer cylinder and is connected to the drive motor. A gear is sleeved on the rotating shaft and meshes with a gear installed at the end of the transmission tube, driving the transmission tube to rotate at the bottom of the partition.

[0006] Furthermore, the transmission pipe is movably connected to the drain pipe on the side of the transfer sleeve. One end of the drain pipe passes through the transfer sleeve and the filter tank and is connected to the sludge storage cylinder. One end of the transmission pipe is connected to the rotating sleeve.

[0007] Furthermore, a threaded sleeve is installed at the bottom of the sealing cover inside the swivel sleeve, and a swivel column is connected to the threaded sleeve. The swivel column is movably connected to the swivel sleeve through a bracket. A stirring blade is uniformly moved on the inner wall of the bottom of the filter tank and located on the movement trajectory of the swivel column. The stirring blade rotates at a fixed angle through the power component at the bottom of the filter tank.

[0008] Furthermore, the bottom of the side wall of the sealing cover is uniformly provided with through holes, the side wall of the sealing cover is provided with a liquid guide port, the top of the sealing cover is bonded with a rubber sealing ring, and a second water pump is installed on the placement rack. The inlet of the second water pump is connected to the top side of the filter tank through a pipe.

[0009] Furthermore, the placement rack is equipped with a main control console for processing data collected from the detection channel, controlling the dosing of the dosing tank, and controlling the backwashing period of the ultrafiltration membrane cartridge.

[0010] The electronic plating wastewater treatment method that also allows for heavy metal recovery is as follows: The neutralization reaction and flocculation sedimentation complete the transfer of most of the sludge. The pretreated Cr and other heavy metal ions are precipitated as hydroxides under alkaline conditions created by adding chemicals in the sedimentation tank. The supernatant is pumped into the filter tank by a water pump. The online heavy metal analyzer located on the detection channel detects the supernatant after the dosing process. When the detected value exceeds the set threshold, the dosage of the front-end reagent is increased. If the value does not exceed the set threshold, the entire backflush period is recalibrated based on the measured value. The supernatant rises along the bottom baffle of the filter tank and gradually passes through the top ultrafiltration membrane cartridge to complete the filtration process. It is then pumped out by the second water pump at the top and driven by the rotating shaft controlled by the drive motor to move the sealing cover connected to the transmission pipe to the bottom of the corresponding ultrafiltration membrane cartridge. At the same time, the rotating column enters the central slot of the stirring blade. As the stirring blade rotates, it pushes the entire sealing cover upward, realizing the connection between the liquid guide port and the transmission pipe side. The water flow at the top of the baffle flows in the opposite direction along the ultrafiltration membrane cartridge into the drain pipe, realizing the online backwashing of the ultrafiltration membrane cartridge and the acquisition of heavy metal concentrate.

[0011] Compared with the prior art, the beneficial effects of the present invention are: In this invention, the movable sealing cover and the rotating sleeve linkage mechanism realize online and precise backwashing of ultrafiltration membrane cartridges and efficient recovery of heavy metal concentrate. The rotating sleeve and sealing cover linkage mechanism designed inside the filter tank, controlled by a drive motor, can precisely move the sealing cover and seal the bottom of the designated ultrafiltration membrane cartridge. During backwashing, the sealing cover moves upward, connecting its liquid guide port with the transmission pipe to form a closed reverse flow channel, allowing clean water to penetrate the ultrafiltration membrane in the reverse direction, powerfully flushing off the heavy metal contaminants attached to the membrane surface. The flushed heavy metal concentrate is collected separately and discharged to the drain pipe instead of being lost with the wastewater. Thus, while completing the efficient cleaning of the membrane module, it also realizes the targeted, concentrated recovery of heavy metal resources, solving the problems of easy membrane clogging and resource waste in traditional filtration devices. This invention integrates an intelligent detection and feedback control system, achieving precision and automation in the dosing and cleaning processes, significantly improving treatment efficiency and stability. By integrating an online detection channel based on anodic stripping voltammetry with the main control console, an intelligent feedback control closed loop is constructed. The system can monitor the heavy metal concentration of the supernatant in the sedimentation tank in real time and automatically adjust the dosage in the dosing tank accordingly to ensure optimal sedimentation. Simultaneously, the monitoring data is also used to dynamically calibrate and adjust the backwashing timing and cycle of the ultrafiltration membrane cartridge. The "on-demand cleaning" strategy based on actual water quality data is more effective in preventing membrane fouling and ensuring long-term stability of membrane flux compared to cleaning at fixed time intervals. It reduces manual intervention and achieves automated and precise operation of the entire process from dosing sedimentation to membrane filtration cleaning, greatly improving the efficiency and reliability of the entire wastewater treatment device. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the overall structure of the electronic electroplating wastewater treatment device with heavy metal recovery function of the present invention. Figure 2 This is a schematic diagram of the main structure of the electronic electroplating wastewater treatment device with heavy metal recovery function of the present invention. Figure 3 This is a rear view schematic diagram of the electronic electroplating wastewater treatment device with heavy metal recovery function of the present invention. Figure 4 This is a schematic diagram of the installation structure of multiple ultrafiltration membrane cartridges inside the filter tank of the present invention; Figure 5 This is a schematic diagram of the bottom screw-on installation structure of the filter tank partition of the present invention; Figure 6 This is a schematic diagram of the mounting structure of the inner sealing cover of the swivel sleeve of the present invention; Figure 7 This is a schematic diagram of the pipeline connection structure from the transfer cylinder to the rotating sleeve of the present invention.

[0013] In the diagram: 1. Placement rack; 2. Sedimentation tank; 3. Dosing tank; 4. Filter tank; 5. Main control panel; 6. Drive motor; 7. Partition plate; 8. Ultrafiltration membrane cartridge; 9. Transfer cylinder; 10. Rotary shaft; 11. Drain pipe; 12. Transmission pipe; 13. Rotary sleeve; 14. Sealing cover; 15. Threaded sleeve; 16. Liquid guide port; 17. Rotary column; 18. Stirring blade; 19. Detection channel; 20. Water pump one; 21. Water pump two. Detailed Implementation

[0014] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0015] Please see Figure 1-7 The present invention provides a technical solution: Example 1: The electronic electroplating wastewater treatment device with heavy metal recovery function is located in the core step of the entire electroplating wastewater treatment process. In the early stage, the electroplating wastewater still needs to go through the wastewater collection and diversion system, the pretreatment and detoxification system. In the early stage, independent pipelines and independent treatment guides are used for wastewater containing different heavy metals to avoid mixing of wastewater of different properties and increase the difficulty of subsequent recycling. Pretreated wastewater is discharged into, for example Figure 1 Inside the sedimentation tank 2 shown, two sedimentation tanks 2 are installed on top of the rack 1 and connected by pipes. A dosing tank 3 is installed on one side of the sedimentation tank 2, and the dosing rate of the dosing tank 3 is controlled by the main control console 5. Figure 2 and Figure 3 A water pump 20 is installed on the placement rack 1 to extract the supernatant in the sedimentation tank 2 on one side and pump it into the filter tank 4 at the bottom. The filter tank 4 is divided into upper and lower sides by the partition 7, such as Figure 4As shown, four ultrafiltration membrane cartridges 8 are installed inside the upper side, and the overall installation is relatively convenient. Simply open the top of the filter tank 4 and screw in the corresponding ultrafiltration membrane cartridges 8. Secondly, a drive motor 6 is installed on the top of the filter tank 4, and a transfer cylinder 9 is set on the partition 7. A rotating shaft 10 is movable on the transfer cylinder 9. When the top of the tank is closed, the drive motor 6 automatically engages with the rotating shaft 10, and the drive motor 6 drives the entire rotating shaft 10 to rotate. like Figure 7 As shown, a bevel gear is provided on the rotating shaft 10 inside the transfer cylinder 9. Similarly, a drain pipe 11 is fixed on the inner wall of the transfer cylinder 9. The drain pipe 11 is connected to the movable transmission pipe 12 on the inner wall of the bottom of the transfer cylinder 9. The gear at the end of the transmission pipe 12 meshes with the gear on the rotating shaft 10. As the rotating shaft 10 rotates, the transmission pipe 12 is driven to rotate at the bottom of the transfer cylinder 9 and the partition plate 7. like Figure 5 As shown, the filter tank 4 is located below the partition 7, and a swivel sleeve 13 is connected to the transmission pipe 12. The main structure of the swivel sleeve 13 is as follows: Figure 6 and Figure 7 As shown, a sealing cover 14 is slidably connected to the inner side. The sealing cover 14 can slide inside the rotating sleeve 13. The rotating sleeve 13 corresponds to the liquid inlet position at the bottom of the four ultrafiltration membrane cartridges 8. During normal use, sewage enters the ultrafiltration membrane cartridge 8 along the bottom of the partition 7. At this time, the rotating sleeve 13 and the sealing cover 14 do not receive the backwash signal and are in a stationary state. Sewage enters the sealing cover 14 at the same time. However, the bottom of the sealing cover 14 is provided with a through hole, and the sealing cover 14 is provided with a liquid guide port 16. However, at this time, the liquid guide port 16 is not connected to the transmission pipe 12 on the rotating sleeve 13, and the sewage cannot enter the drain pipe 11 on the side of the transfer cylinder 9 through the transmission pipe 12. As the entire sealing cover 14 rises to complete the removal of the ultrafiltration membrane cartridge 8, the ultrafiltration membrane cartridge 8 removed on one side and the sealing cover 14 form a complete communication path. The through hole at the bottom of the sealing cover 14 is blocked by the screw sleeve 13. The liquid guide port 16 during the lifting process will also be connected to the transmission pipe 12. At this time, the drain pipe 11 is opened, and the water pressure is used to reverse the water flow from the outside of the ultrafiltration membrane cartridge 8 to the inside of the membrane cartridge, flushing the adhered sludge into the transfer cylinder 9. Finally, the concentrated sludge is discharged through the drain pipe 11 for subsequent unified treatment. The cleaning of each ultrafiltration membrane cartridge 8 is performed sequentially, thus not affecting the normal operation of other ultrafiltration membrane cartridges 8 and improving the overall wastewater treatment efficiency. Simultaneously, the processing time of each ultrafiltration membrane cartridge 8 is controlled by an external main control panel 5, which requires the monitoring channel 19 to collect relevant supernatant data, such as... Figure 3As shown, the online heavy metal analyzer installed on detection channel 19 adopts the anodic stripping voltammetry method. The anodic stripping voltammetry method has high sensitivity to certain heavy metals and can realize multi-parameter measurement. The measured value is compared with the calibration threshold. If the measured value is high, it indicates that the front-end supernatant treatment is incomplete. The measured value is reduced by controlling the amount of chemical added by the dosing tank 3. If the measured value is lower than the threshold, the backwashing time is calibrated according to the threshold. For example, if the measured value is in the range A, the calibration backwashing interval is 20 minutes. When the measured value enters the range B, B is greater than A and less than the threshold, the backwashing interval needs to be shortened. Meanwhile, the entire ultrafiltration membrane cartridge 8 is regularly subjected to CEB and CIP cleaning using cleaning agents such as hydrochloric acid, sodium hypochlorite, and sodium hydroxide. When the supernatant is not discharged, it is discharged in reverse through the drain pipe 11 into each ultrafiltration membrane cartridge 8 to complete the deep cleaning of the inner wall of the membrane cartridge and maintain membrane performance.

[0016] Example 2: Regarding the height control of the entire sealing cover 14 within the sleeve 13, as follows... Figure 7 As shown, a threaded sleeve 15 is fixed at the bottom of the sealing cover 14. A rotating post 17 is internally threaded onto the threaded sleeve 15. The rotating post 17 is movably connected to the bracket on the rotating sleeve 13. Figure 6 It can be understood that the bottom of the filter tank 4 is equipped with stirring blades 18 corresponding to the ultrafiltration membrane cartridge 8. Each stirring blade 18 is composed of two plates, with a channel formed between the plates. The rotating column 17, which is corresponding to the stirring blade 18, is located on the trajectory of the four channels. As long as the rotating column 17 is kept at a specific angle, the square area at the bottom of the rotating column 17 will be inserted into the center of the channel of the stirring blade 18 as the entire rotating sleeve 13 rotates. By rotating the sleeve 13 at a fixed angle and the entire stirring blade 18 rotating, the entire rotating column 17 is driven to rotate within the threaded sleeve 15. The rotating column 17 is limited by the sleeve 13, causing the sealing cover 14 connected to the threaded sleeve 15 to move upward, thus completing the bottom cover removal of the ultrafiltration membrane cartridge 8 at the corresponding position. At the same time, the overall sealing performance is improved. A rubber ring is installed on the top of the sealing cover 14. The tighter the compression, the better the seal. With the opening of the single-sided drain pipe 11, the corresponding ultrafiltration membrane cartridge 8 is flushed by water pressure. The wastewater is discharged into the drain pipe 11 along the transmission pipe 12. The entire backwashing time is controlled within 1 minute to remove contaminants from the membrane surface. The water flow intercepted by the ultrafiltration membrane cartridge 8 gradually rises and is eventually drawn out by the water pump 21 on the placement rack 1 for further, more advanced treatment.

[0017] The above description is merely an example and illustration of the structure of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described, or use similar methods to replace them, as long as they do not deviate from the structure of the invention or exceed the scope defined in the claims, all of which should fall within the protection scope of the present invention.

[0018] In the description of this specification, the references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any suitable manner in one or more embodiments or examples. The preferred embodiments of the present invention disclosed above are merely for the purpose of illustrating the present invention. The preferred embodiments do not exhaustively describe all details, nor do they limit the invention to specific implementations. Obviously, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to well understand and utilize the present invention. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. An electronic electroplating wastewater treatment device with heavy metal recovery function, comprising a placement rack (1), a sedimentation tank (2), and a filter tank (4), wherein the sedimentation tank (2) is symmetrically installed on the top of the placement rack (1), and the filter tank (4) is fixed on the placement rack (1) and located at the bottom of the sedimentation tank (2) on one side, characterized in that, A water pump (20) is installed on the placement rack (1). The inlet of the water pump (20) is connected to the top side of the single-sided sedimentation tank (2) through a pipe, and the outlet of the water pump (20) is connected to the bottom side of the filter tank (4) through a pipe. The filter tank (4) is fixedly connected to a partition (7), and ultrafiltration membrane cartridges (8) are evenly installed on the partition (7). A transfer cylinder (9) is also installed on the partition (7) on the side of the ultrafiltration membrane cartridge (8). A transmission tube (12) is movably connected inside the transfer cylinder (9), and one end of the transmission tube (12) passes through the partition (7) and is fixedly connected to a rotating sleeve (13). A sealing cover (14) is slidably connected inside the rotating sleeve (13). The sealing cover (14) is correspondingly set to the ultrafiltration membrane cartridges (8) installed on the side of the partition (7) and is used for receiving and transporting heavy metal concentrate during backwashing.

2. The electronic electroplating wastewater treatment device with heavy metal recovery function according to claim 1, characterized in that, The bottoms of the two sedimentation tanks (2) are connected by a pipe. A dosing tank (3) is installed on the top of the sedimentation tank (2) on one side. A detection channel (19) is installed on the placement rack (1). The detection channel (19) is located at the front end of the water inlet pipe of the water pump (20). The equipment installed on the side of the detection channel (19) uses the anodic stripping voltammetry method to perform online detection of the supernatant of the sedimentation tank (2).

3. The electronic electroplating wastewater treatment device with heavy metal recovery function according to claim 2, characterized in that, The filter tank (4) is equipped with a drive motor (6) at the top, and a rotating shaft (10) is installed inside the storage cylinder (9). The end of the rotating shaft (10) passes through the storage cylinder (9) and is connected to the drive motor (6). A gear is sleeved on the rotating shaft (10) and meshes with a gear installed at the end of the transmission tube (12). The drive transmission tube (12) is rotated at the bottom of the partition plate (7).

4. The electronic electroplating wastewater treatment device with heavy metal recovery function according to claim 3, characterized in that, The transmission pipe (12) is movably connected to the drain pipe (11) on the side of the transfer sleeve. One end of the drain pipe (11) passes through the transfer sleeve and the filter tank (4) and is connected to the upper sludge storage cylinder. One end of the transmission pipe (12) is connected to the rotating sleeve (13).

5. The electronic electroplating wastewater treatment device with heavy metal recovery function according to claim 4, characterized in that, A threaded sleeve (15) is installed at the bottom of the sealing cover (14) inside the sleeve (13). A rotating column (17) is threadedly connected to the threaded sleeve (15), and the rotating column (17) is movably connected to the sleeve (13) through a bracket. A stirring blade (18) is uniformly moved on the bottom inner wall of the filter tank (4) and on the movement trajectory of the rotating column (17). The stirring blade (18) is rotated at a fixed angle by the power assembly at the bottom of the filter tank (4).

6. The electronic electroplating wastewater treatment device with heavy metal recovery function according to claim 5, characterized in that, The sealing cover (14) has through holes evenly opened at the bottom of its side wall, and a liquid guide port (16) is opened on the side wall of the sealing cover (14). A rubber sealing ring is attached to the top of the sealing cover (14). A water pump (21) is installed on the placement rack (1). The water inlet of the water pump (21) is connected to the top side of the filter tank (4) through a pipe.

7. The electronic electroplating wastewater treatment device with heavy metal recovery function according to claim 6, characterized in that, The placement rack (1) is equipped with a main control console (5) for data processing of the detection channel (19), and for controlling the dosing of the dosing tank (3) and the backwashing period of the ultrafiltration membrane cartridge (8).

8. The electronic electroplating wastewater treatment device with heavy metal recovery function according to claim 7, characterized in that, The following is a method for treating electronic plating wastewater that also allows for heavy metal recovery: The neutralization reaction flocculation and sedimentation completes the transfer of most of the sludge. The pretreated Cr and other heavy metal ions are added to the sedimentation tank (2) to form hydroxide precipitates under alkaline conditions. The supernatant is pumped into the filter tank (4) by water pump (20). The online heavy metal analyzer located on the detection channel (19) detects the supernatant after the dosing treatment. When the detection value exceeds the set threshold, the dosage of the front-end reagent is increased. When the value does not exceed the set threshold, the entire backflush period is recalibrated according to the measured value. The supernatant rises along the bottom partition (7) of the filter tank (4) and gradually passes through the top ultrafiltration membrane cartridge (8) to complete the filtration. Then it is pumped out by the top water pump (21) and driven by the rotating shaft (10) controlled by the drive motor (6) to move the sealing cover (14) connected to the transmission pipe (12) to the bottom of the corresponding ultrafiltration membrane cartridge (8). At the same time, the rotating column (17) enters the center slot of the stirring blade (18). As the stirring blade (18) rotates, it pushes the entire sealing cover (14) to move upward, so that the liquid guide port (16) is connected to the side of the transmission pipe (12). The water flow at the top of the partition (7) flows in the opposite direction along the ultrafiltration membrane cartridge (8) into the drain pipe (11), so as to realize the online backwashing of the ultrafiltration membrane cartridge (8) and the acquisition of heavy metal concentrate.

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